1/* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16package com.example.android.supportv7.util; 17 18import android.os.Bundle; 19import android.view.KeyEvent; 20import android.view.LayoutInflater; 21import android.view.View; 22import android.view.ViewGroup; 23import android.view.inputmethod.EditorInfo; 24import android.widget.CheckBox; 25import android.widget.CompoundButton; 26import android.widget.EditText; 27import android.widget.TextView; 28 29import androidx.appcompat.app.AppCompatActivity; 30import androidx.recyclerview.widget.LinearLayoutManager; 31import androidx.recyclerview.widget.RecyclerView; 32import androidx.recyclerview.widget.SortedList; 33import androidx.recyclerview.widget.SortedListAdapterCallback; 34 35import com.example.android.supportv7.R; 36 37/** 38 * A sample activity that uses {@link SortedList} in combination with RecyclerView. 39 */ 40public class SortedListActivity extends AppCompatActivity { 41 private RecyclerView mRecyclerView; 42 private LinearLayoutManager mLinearLayoutManager; 43 private SortedListAdapter mAdapter; 44 @Override 45 protected void onCreate(Bundle savedInstanceState) { 46 super.onCreate(savedInstanceState); 47 setContentView(R.layout.sorted_list_activity); 48 mRecyclerView = findViewById(R.id.recycler_view); 49 mRecyclerView.setHasFixedSize(true); 50 mLinearLayoutManager = new LinearLayoutManager(this); 51 mRecyclerView.setLayoutManager(mLinearLayoutManager); 52 mAdapter = new SortedListAdapter(getLayoutInflater(), 53 new Item("buy milk"), new Item("wash the car"), 54 new Item("wash the dishes")); 55 mRecyclerView.setAdapter(mAdapter); 56 mRecyclerView.setHasFixedSize(true); 57 final EditText newItemTextView = findViewById(R.id.new_item_text_view); 58 newItemTextView.setOnEditorActionListener(new TextView.OnEditorActionListener() { 59 @Override 60 public boolean onEditorAction(TextView textView, int id, KeyEvent keyEvent) { 61 if (id == EditorInfo.IME_ACTION_DONE && 62 (keyEvent == null || keyEvent.getAction() == KeyEvent.ACTION_DOWN)) { 63 final String text = textView.getText().toString().trim(); 64 if (text.length() > 0) { 65 mAdapter.addItem(new Item(text)); 66 } 67 textView.setText(""); 68 return true; 69 } 70 return false; 71 } 72 }); 73 } 74 75 private static class SortedListAdapter extends RecyclerView.Adapter<TodoViewHolder> { 76 SortedList<Item> mData; 77 final LayoutInflater mLayoutInflater; 78 public SortedListAdapter(LayoutInflater layoutInflater, Item... items) { 79 mLayoutInflater = layoutInflater; 80 mData = new SortedList<Item>(Item.class, new SortedListAdapterCallback<Item>(this) { 81 @Override 82 public int compare(Item t0, Item t1) { 83 if (t0.mIsDone != t1.mIsDone) { 84 return t0.mIsDone ? 1 : -1; 85 } 86 int txtComp = t0.mText.compareTo(t1.mText); 87 if (txtComp != 0) { 88 return txtComp; 89 } 90 if (t0.id < t1.id) { 91 return -1; 92 } else if (t0.id > t1.id) { 93 return 1; 94 } 95 return 0; 96 } 97 98 @Override 99 public boolean areContentsTheSame(Item oldItem, 100 Item newItem) { 101 return oldItem.mText.equals(newItem.mText); 102 } 103 104 @Override 105 public boolean areItemsTheSame(Item item1, Item item2) { 106 return item1.id == item2.id; 107 } 108 }); 109 for (Item item : items) { 110 mData.add(item); 111 } 112 } 113 114 public void addItem(Item item) { 115 mData.add(item); 116 } 117 118 @Override 119 public TodoViewHolder onCreateViewHolder(final ViewGroup parent, int viewType) { 120 return new TodoViewHolder ( 121 mLayoutInflater.inflate(R.layout.sorted_list_item_view, parent, false)) { 122 @Override 123 void onDoneChanged(boolean isDone) { 124 int adapterPosition = getAdapterPosition(); 125 if (adapterPosition == RecyclerView.NO_POSITION) { 126 return; 127 } 128 mBoundItem.mIsDone = isDone; 129 mData.recalculatePositionOfItemAt(adapterPosition); 130 } 131 }; 132 } 133 134 @Override 135 public void onBindViewHolder(TodoViewHolder holder, int position) { 136 holder.bindTo(mData.get(position)); 137 } 138 139 @Override 140 public int getItemCount() { 141 return mData.size(); 142 } 143 } 144 145 abstract private static class TodoViewHolder extends RecyclerView.ViewHolder { 146 final CheckBox mCheckBox; 147 Item mBoundItem; 148 public TodoViewHolder(View itemView) { 149 super(itemView); 150 mCheckBox = (CheckBox) itemView; 151 mCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { 152 @Override 153 public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { 154 if (mBoundItem != null && isChecked != mBoundItem.mIsDone) { 155 onDoneChanged(isChecked); 156 } 157 } 158 }); 159 } 160 161 public void bindTo(Item item) { 162 mBoundItem = item; 163 mCheckBox.setText(item.mText); 164 mCheckBox.setChecked(item.mIsDone); 165 } 166 167 abstract void onDoneChanged(boolean isChecked); 168 } 169 170 private static class Item { 171 String mText; 172 boolean mIsDone = false; 173 final public int id; 174 private static int idCounter = 0; 175 176 public Item(String text) { 177 id = idCounter ++; 178 this.mText = text; 179 } 180 } 181} 182